You can do what you want, but not by the method you propose i.e.:
{IF {Mergefield Fieldname1} <> "" "{IF {Mergefield Fieldname2} <> ""
"{Mergefield Fieldname3}" ""}""}

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Graham Mayor - Word MVP
E-mail gmayor@mvps.org
Web site www.gmayor.com
Word MVP web site www.mvps.org/word
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> Hi
>
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>
> If so your help would be appreciated (Word 97)